In order to ensure full heat exchange of an air conditioner, a fin of a heat exchanger of the air conditioner often is designed as a plurality layers of compact sheets, where a gap between the sheets is only 1 to 2 mm, and various embossing or fractures are added to the fin of a heat exchanger so as to increase a heat exchange area. When the air conditioner is operating, a lot of air flows through the heat exchanger to perform a heat exchange. Various dusts and impurities in the air adhere to the heat exchanger; this affects effects of the heat exchanger, breeds bacterium easily, brings a peculiar smell to the air conditioner, and even affects user health. At this time, the heat exchanger of the air conditioner needs to be cleaned.
At present, an outdoor unit is cleaned in a long time interval or is never cleaned. While being cleaned manually, the heat exchanger is difficult to be cleaned because the heat exchanger is close to a wall. As a result, the heat exchanger is not completely cleaned. Cleaning the heat exchanger by extending a foreign object may cause sheets of the fin to fall down, so as to further affect heat exchanging effects of the heat exchanger, and shorten service life thereof.
In the prior art, the heat exchanger is cleaned by using manners of frosting and defrosting the heat exchanger. However, when self cleaning to an indoor heat exchanger or an outdoor heat exchanger is switched, an evaporating temperature and an evaporating pressure during a self cleaning process are low. Therefore, a difference between a high pressure and a low pressure of the air conditioner is excessive, and a compressor is shocked during a process of switching a four-way valve. As a result, operation of the air conditioner is unstable.